3 Answers
3

I asked that question at the SharePoint Conference and they said there shouldn't be any performance difference. I agree with you though, I would think that unpackaging the wsp, opening a new process, and returning the result would means slower page loads on whatever is using that functionality.

Correct, I have experienced a slow down too. This is down to how sandboxing works - creating a copy of the page object, running the sandbox with that, then merging back to the parent page object.
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MauroNov 17 '14 at 11:42